John Turri

Contemporary philosophers nearly unanimously endorse knowledge reliabilism, the view that knowledge must be reliably produced. Leading reliabilists have suggested that reliabilism draws support from patterns in ordinary judgments and intuitions about knowledge, luck, reliability, and counterfactuals. That is, they have suggested a proto-reliabilist hypothesis about “commonsense” or “folk” epistemology. This paper reports nine experimental studies (N = 1262) that test the proto-reliabilist hypothesis by testing four of its principal implications. The main findings are that (a) commonsense fully embraces the possibility of unreliable knowledge, (b) knowledge judgments are surprisingly insensitive to information about reliability, (c) “anti-luck” intuitions about knowledge have nothing to do with reliability specifically, and (d) reliabilists have mischaracterized the intuitive counterfactual properties of knowledge and their relation to reliability. When combined with the weakness of existing arguments for reliabilism and the recent emergence of well supported alternative views that predict the widespread existence of unreliable knowledge, the present findings are the final exhibit in a conclusive case for abandoning reliabilism in epistemology. I introduce an alternative theory of knowledge, abilism, which out-performs reliabilism and well explains all the available evidence.

This paper clarifies and evaluates a premise of William Alston’s argument in Perceiving God. The premise in question: if it is practically rational to engage in a doxastic practice, then it is epistemically rational to suppose that said practice is reliable. I first provide the background needed to understand how this premise fits into Alston’s main argument. I then present Alston’s main argument, and proceed to clarify, criticize, modify, and ultimately reject Alston’s argument for the premise in question. Without this premise, Alston’s main argument fails.

The Knowledge Account of Assertion (KAA) says that knowledge is the norm of assertion: you may assert a proposition only if you know that it’s true. The primary support for KAA is an explanatory inference from a broad range of linguistic data. The more data that KAA well explains, the stronger the case for it, and the more difficult it is for the competition to keep pace. In this paper we critically assess a purported new linguistic datum, which, it has been argued, KAA well explains. We argue that KAA does not well explain it

Researchers have debated whether knowledge or certainty is a better candidate for the norm of assertion. Should you make an assertion only if you know it's true? Or should you make an assertion only if you're certain it's true? If either knowledge or certainty is a better candidate, then this will likely have detectable behavioral consequences. I report an experiment that tests for relevant behavioral consequences. The results support the view that assertability is more closely linked to knowledge than to certainty. In multiple scenarios, people were much more willing to allow assertability and certainty to come apart than to allow assertability and knowledge to come apart

Assertion is fundamental to our lives as social and cognitive beings. Philosophers have recently built an impressive case that the norm of assertion is factive. That is, you should make an assertion only if it is true. Thus far the case for a factive norm of assertion been based on observational data. This paper adds experimental evidence in favor of a factive norm from six studies. In these studies, an assertion’s truth value dramatically affects whether people think it should be made. Whereas nearly everyone agreed that a true assertion supported by good evidence should be made, most people judged that a false assertion supported by good evidence should not be made. The studies also suggest that people are consciously aware of criteria that guide their evaluation of assertions. Evidence is also presented that some intuitive support for a non-factive norm of assertion comes from a surprising tendency people have to misdescribe cases of blameless rule-breaking as cases where no rule is broken.

According to factive accounts of the norm of belief and decision-making, you should not believe or base decisions on a falsehood. Even when the evidence misleadingly suggests that a false proposition is true, you should not believe it or base decisions on it. Critics claim that factive accounts are counterintuitive and badly mischaracterize our ordinary practice of evaluating beliefs and decisions. This paper reports four experiments that rigorously test the critic’s accusations and the viability of factive accounts. The results undermine the accusations and provide the best evidence yet of factive norms of belief and decision-making. The results also help discriminate between two leading candidates for a factive norm: truth and knowledge. Knowledge is the superior candidate.

Recent work has assumed that the normativity associated with assertion differs from the normativity of morality, practical rationality, etiquette, and legality. That is, whether an assertion “should” be made is not merely a function of these other familiar sorts of normativity and is especially connected to truth. Some researchers have challenged this assumption of distinctive normativity. In this paper I report two experiments that test the assumption. Participants read a brief story, judged whether an assertion should be made, and rated several other qualities of the assertion, including its truth value, morality, rationality, etiquette, legality, and folly. Of these qualities, truth value most strongly predicted assertability. The findings support the assumption of distinctive normativity and provide further evidence that the norm of our social practice of assertion is factive.

Infinitism is an ancient view in epistemology about the structure of knowledge and epistemic justification, according to which there are no foundational reasons for belief. The view has never been popular, and is often associated with skepticism, but after languishing for centuries it has recently begun a resurgence. Ad Infinitum presents new work on the topic by leading epistemologists. They shed new light on infinitism's distinctive strengths and weaknesses, and address questions, new and old, about its account of justification, reasoning, epistemic responsibility, disagreement, and trust, among other important issues. The volume clarifies the relationship between infinitism and other epistemological views, such as skepticism, coherentism, foundationalism and contextualism, and it offers novel perspectives on the metaphysics, epistemology, and ethics of regresses and reasons.

In a single-iteration fake barn case, the agent correctly identifies an object of interest on the first try, despite the presence of nearby lookalikes that could have mislead her. In a multiple-iteration fake barn case, the agent first encounters several fakes, misidentifies each of them, and then encounters and correctly identifies a genuine item of interest. Prior work has established that people tend to attribute knowledge in single-iteration fake barn cases, but multiple-iteration cases have not been tested. However, some theorists contend that multiple-iteration cases are more important and will elicit a strong tendency to deny knowledge. Here I report a behavioural experiment investigating knowledge judgments in multiple-iteration fake barn cases. The main finding is that people tend to attribute knowledge in these cases too. Ironically, the results indicate that the presence of fakes could prevent iterated errors from lowering knowledge attributions. The results also provide evidence that ordinary knowledge attributions are based on attributions of cognitive ability.